Metabolic Mechanisms of Intertemporal Choice, Delay Discounting, and Impulsiveness

在这个项目中，主要研究者将在进化心理学和生活史理论的跨学科框架内研究跨期选择、延迟（未来）折扣和冲动的代谢机制。在跨期选择中，当人们认为现在的东西比未来的东西更有价值时，当他们更喜欢小而快的奖励（SS）而不是大而晚的奖励（LL）时，他们会对未来或延迟的奖励进行贴现。最近的研究揭示了血糖水平波动和延迟折扣之间的新联系。研究表明，含糖饮料减少了延迟折扣，使LL选项更具吸引力，而无糖饮料增加了延迟折扣，使SS选项更受欢迎。这一观察结果与葡萄糖是认知资源的假设以及血糖水平是能量预算状态的信号的假设是一致的。这项资助的研究将检查身体葡萄糖水平的变化，以及类固醇激素的变化和代谢率的季节性变化如何影响延迟折扣和决策者的冲动，以确定这些假设中哪一个更能解释血糖对延迟折扣的影响。另外的实验将检验代谢条件下生存的现在取向和交配和繁殖的未来取向之间的权衡。这个项目具有广泛的应用意义。延迟满足的能力已经被证明会导致更少的精神病理，更好的成绩，更少的物质使用，在生活中更全面的成功。因此，灌输更多的延迟满足将导致更有成效和更健康的生活。通过识别增加或减少延迟折扣和冲动的代谢条件，我们将能够帮助设计更好的干预成瘾和强迫行为。从拟议的研究中获得的知识应该为促进积极的健康行为提供指导。

In this project the Principal Investigators will examine metabolic mechanisms underlying intertemporal choice, delay (future) discounting, and impulsiveness within an interdisciplinary framework of evolutionary psychology and life-history theory. People discount the future or delayed rewards when they value present goods over future goods and when they prefer a smaller and sooner (SS) reward to a larger and later (LL) reward in making intertemporal choices. Recent research has revealed a novel link between fluctuating blood glucose levels and delay discounting. The study showed that a sugar drink reduced delay discounting, making the LL options more attractive whereas a diet drink increased delay discounting, making the SS options more preferable. This observation is consistent with the hypothesis that glucose is a cognitive resource and with the hypothesis that blood glucose level is a signal of energy budget status. The funded research will examine how bodily changes in glucose levels, along with variations in steroid hormones and seasonal changes in metabolic rates, affect delay discounting and impulsiveness of decision makers to determine which of these hypotheses better accounts for the effects of blood glucose on delay discounting. Additional experiments will examine tradeoffs between present-orientation for survival and future-orientation for mating and reproduction as a function of metabolic conditions. This project has broad applied implications. The ability to delay gratification has been shown to lead to less psychopathology, better grades, less substance use, and more overall success in life. Thus, instilling greater delay of gratification would lead to more productive and healthier lives. By identifying metabolic conditions that increase or decrease delay discounting and impulsiveness, we would be able to help design better interventions for addictive and obsessive-compulsive behaviors. The knowledge gained from the proposed studies should provide guidance for promoting positive health behavior.